1. Field of the Invention
The invention relates to a selectably operable rotary contact switch. More particularly, the invention relates to a momentary rotary switch having a torsion spring that is reduced in diameter whenever the switch selector is rotated, thereby signaling a microprocessor to power a particular circuit or a step in a routine.
2. Background Art
Modern handheld medical devices typically perform more than one electronically controlled function. Most of these devices control the activation of a particular function by a simple on/off switch. The use of multiple switches to control multiple functions in a handheld multi-functional medical device is problematic. Handheld devices must be simple and comfortable to use. Having multiple switches located on a small handheld device often leads to difficulty in the operation of the proper switch at the right time for the operator and may lead to confusion for the operator of the device.
Thus, there is a need for an easy to operate multi-functional switch that can control multiple functions in a small handheld device. For example, the use of a small medical device for a close-up visual examination must be simple to use with one hand.